Abstract: The edge effects would happen when a workpiece extends beyond a polishing tool, which could lead to low polishing efficiency. So a new skin model, representing the nonlinear pressure distribution, was proposed to avoid the negative pressure and to calculate the amount of removed materials for the case of a circular tool that polishes a circular workpiece. A material removal amount model was established considering workpiece radius, workpiece-tool center distance and speed ratio. Its simulations show that good surface figures could be achieved by choosing proper values for the latter two parameters based on that model.